Transient ischemic attack without self-awareness of symptoms witnessed by bystanders: analysis of the PROMISE-TIA registry.

BACKGROUND AND PURPOSE: A transient ischemic attack (TIA) can occur without self-awareness of symptoms. We aimed to investigate characteristics of patients with a tissue-based diagnosis of TIA but having no self-awareness of their symptoms and whose symptoms were witnessed by bystanders. METHODS: We used data from the multicenter registry of 1414 patients with a clinical diagnosis of TIA. For patients without evidence of ischemic lesions on imaging, clinical characteristics were compared between patients with and without self-awareness of their TIA symptoms. RESULTS: Among 896 patients (559 men, median age of 70 years), 59 (6.6%) were unaware of their TIA symptoms, but had those symptoms witnessed by bystanders. Patients without self-awareness of symptoms were older and more frequently female, and more likely to have previous history of stroke, premorbid disability, and atrial fibrillation, but less likely to have dyslipidemia than those with self-awareness. Patients without self-awareness of symptoms arrive at hospitals earlier than those with self-awareness (P < 0.001). ABCD2 score was higher in patients without self-awareness of symptoms than those with self-awareness (median 5 vs. 4, P = 0.002). Having no self-awareness of symptoms was a significant predictor of ischemic stroke within 1 year after adjustment for sex, ABCD2 score, and onset to arrival time (hazard ratio = 2.44, 95% confidential interval: 1.10-4.83), but was not significant after further adjustment for arterial stenosis or occlusion. CONCLUSIONS: Patients with a TIA but having no self-awareness of their symptoms might have higher risk of subsequent ischemic stroke rather than those with self-awareness, suggesting urgent management is needed even if patients have no self-awareness of symptoms.

Risk Factors.

Studies investigating risk factors for intracranial atherosclerosis (ICAS) have been infrequent. However, due to recent availability of non-invasive vascular imaging techniques that can assess intracranial cerebral arteries, there are a growing number of studies on risk factors for ICAS. Conventional vascular risk factors such as hypertension, diabetes, hypercholesterolemia and cigarette smoking are risk factors for ICAS. However, it remains uncertain whether there is a difference in risk factors between ICAS and extracranial atherosclerosis (ECAS). It also remains unclear why ICAS is more common in Asians and Blacks than in Caucasians. Although we reviewed available evidences on these differences, the review was limited because studies were heterogeneous in the definition of risk factors, diagnostic method, and characteristics of study subjects (hospitalized vs. community) or cerebral vessels (symptomatic vs. asymptomatic). Nevertheless, it seems that hypercholesterolemia is more closely associated with ECAS than ICAS. The difference in hypercholesterolemia prevalence is one of the main reasons for racial differences in the location of cerebral atherosclerosis. Intracranial arteries contain higher antioxidant level than extracranial arteries and may be more vulnerable to risk factors that deplete antioxidants (e.g., metabolic syndrome and diabetes mellitus). Intracranial arteries may be more vulnerable to factors associated with hemodynamic stress (e.g., advanced, salt-retaining hypertension and arterial tortuosity) because of a smaller diameter, thinner media and adventitia, and fewer elastic medial fibers than extracranial arteries. Additionally, non-atherosclerotic arterial diseases (e.g., moyamoya disease) that commonly occur in the intracranial arteries of East Asians may contaminate the reports of ICAS cases. Various genes, including RNF 213, might also explain racial differences in atherosclerotic location. Prospective, well-designed risk factor and genetic studies should be performed in a homogeneous group of patients with diverse ethnicities. These efforts are essential in the prevention of atherosclerotic diseases based on adequate knowledge of the risk factors and pathogenesis.

Impact of B-type natriuretic peptide (BNP) on development of atrial fibrillation in people with Type 2 diabetes.

AIMS: To examine if a simple biomarker can identify people with diabetes who are at high risk of atrial fibrillation. METHODS: A retrospective cohort study was conducted at a single centre in people with Type 2 diabetes referred to our department between January 2000 and December 2007. In 517 consecutive people without any history, signs or symptoms of atrial fibrillation at baseline, the association between baseline B-type natriuretic peptide level and future atrial fibrillation incidence was examined, with adjustments for other potentially confounding factors. RESULTS: A total of 28 people were diagnosed with new-onset atrial fibrillation during a median 6-year follow-up. When people were categorized into three groups according to B-type natriuretic peptide clinical thresholds (20 and 100 pg/ml), hazard ratios for the development of atrial fibrillation in the middle and highest B-type natriuretic peptide groups were 2.8 and 9.4, respectively, compared with the lowest B-type natriuretic peptide group. Time-dependent receiver-operating curve analysis identified a threshold for B-type natriuretic peptide to detect atrial fibrillation development of 52.8 pg/ml (sensitivity 75.2%, specificity 68.8%). The B-type natriuretic peptide predictive value was independent of and similar to that of left atrial size and ventricular dimension. CONCLUSION: In people with Type 2 diabetes, high baseline B-type natriuretic peptide levels were significantly associated with future atrial fibrillation development.

The relationship between the pre-admission CHA2DS2-VASc score and proximal artery occlusion in patients with acute stroke and atrial fibrillation.

BACKGROUND AND PURPOSE: The CHA2DS2-VASc score is associated with severity and outcome of ischaemic stroke in patients with atrial fibrillation (AF). It was hypothesized that a high CHA2DS2-VASc score was related to severity and outcome because of its association with proximal artery occlusion (PAO). This study aimed to elucidate the relationship between the CHA2DS2-VASc score and PAO and to determine whether the effect of the CHA2DS2-VASc score on severity or outcome is independent of PAO. METHODS: Acute stroke patients with AF were retrospectively enrolled. PAO was defined as occlusion at the internal carotid artery or proximal middle cerebral artery on admission magnetic resonance angiography. Multivariable analyses were performed to identify independent factors associated with PAO and determine the associations of the CHA2DS2-VASc score with the initial National Institutes of Health Stroke Scale (NIHSS) score and poor functional outcome (discharge modified Rankin scale score 4-6). RESULTS: In all, 213 patients [102 women; median age 80 (interquartile range 71-86) years; NIHSS score 16 (9-22)] were enrolled. On multivariable analysis, the CHA2DS2-VASc score (odds ratio 1.40, 95% confidence interval 1.12-1.76 per 1 point) was independently associated with PAO and correlated with the initial NIHSS score (standardized coefficient 0.198, P = 0.017). This association was not significant after further adjustment for PAO (0.080, P = 0.241). The CHA2DS2-VASc score was independently related to poor outcome even adjusted for PAO (odds ratio 1.39, 95% confidence interval 1.03-1.88). CONCLUSION: The CHA2DS2-VASc score was associated with PAO in acute ischaemic stroke patients with AF. The CHA2DS2-VASc score may be correlated with the NIHSS score through the presence of PAO and with poor functional outcome independently of PAO.

Simple clinical predictors of stroke outcome based on National Institutes of Health Stroke scale score during 1-h recombinant tissue-type plasminogen activator infusion.

BACKGROUND AND PURPOSE: An index for predictors of stroke outcome was determined based on the National Institutes of Health Stroke Scale (NIHSS) scores during 1-h intravenous administration of recombinant tissue-type plasminogen activator (rt-PA). METHODS: Stroke patients with baseline NIHSS score ≥8 and occlusion at the internal carotid or middle cerebral arteries (ICA, MCA) were retrospectively studied from a prospective single-center registry. NIHSS scores and inverse change from baseline scores (ΔNIHSS) were assessed at 30 min and 1 h after rt-PA infusion. Patients were divided into two groups according to arterial occlusion sites: group P, ICA or proximal M1; and group D, distal M1 or M2. A modified Rankin Scale score of 2-6 at 3 months was defined as an unfavorable outcome. RESULTS: In all 108 patients, the cutoff NIHSS score predicting unfavorable outcome was ≥12 and cutoff ΔNIHSS scores were ≤2 at both 30 min and 1 h. In group P (n = 36), the cutoff NIHSS score was ≥14 at both 30 min and 1 h and cutoff ΔNIHSS scores were ≤1 at 30 min and ≤2 at 1 h. Unfavorable outcome was seen in all patients with NIHSS1 h ≥ 14, ΔNIHSS30 min ≤ 1 and ΔNIHSS1 h ≤ 2. In group D (n = 72), the cutoff NIHSS scores were ≥12 at both 30 min and 1 h, and cutoff ΔNIHSS scores were ≤2 at 30 min and ≤7 at 1 h; 90% of patients with unfavorable outcome showed ΔNIHSS1 h ≤ 7. CONCLUSION: NIHSS and ΔNIHSS during 1-h rt-PA infusion seemed predictive of 3-month outcome when the site of arterial occlusion was identified prior to rt-PA.

Intravenous thrombolysis for patients with reverse magnetic resonance angiography and diffusion-weighted imaging mismatch: SAMURAI and NCVC rt-PA Registries.

BACKGROUND AND PURPOSE: The characteristics of reverse magnetic resonance angiography and diffusion-weighted imaging (MRA-DWI) mismatch (RMM), defined as a large DWI lesion in the absence of major artery occlusion (MAO), remain unknown, especially in patients treated with intravenous recombinant tissue plasminogen activator (rt-PA). METHODS: Patients with stroke in the middle cerebral artery territory were included. Early ischaemic changes (EIC) were assessed with the Alberta Stroke Program Early CT Score on DWI (DWI-ASPECTS). All patients were divided into four groups based on the presence of MAO and a DWI-ASPECTS cut-off value of <7. RMM was defined as DWI-ASPECTS <7 without MAO. Clinical characteristics, symptomatic intracerebral hemorrhage (sICH) and favorable functional outcome (modified Rankin Scale score 0-2) at 90 days were compared amongst the four groups. RESULTS: Of the 486 patients enrolled (167 women, median age 74 years, median initial National Institutes of Health Stroke Scale score 13), reverse MRA-DWI mismatch was observed in 24 (5%). Of the clinical characteristics, cardioembolism was the only factor that was independently associated with RMM [odds ratio (OR) 5.49, 95% confidence interval (CI) 1.25-24.1]. Multivariable analyses revealed that patients with RMM more commonly had sICH than those with DWI-ASPECTS ≥ 7 irrespective of the presence (OR 5.44, 95% CI 1.13-26.1) or absence (13.1, 2.07-83.3) of MAO, and they had a more favorable functional outcome than those with DWI-ASPECTS < 7 plus MAO (7.45, 2.39-23.2). CONCLUSION: RMM was observed in 5% of patients treated with rt-PA and associated with cardioembolism. Patients with RMM may benefit from thrombolysis compared with those with EIC with MAO, although increment in the rate of sICH is a concern.

Run-up to participation in ATACH II in Japan.

Intracerebral hemorrhage (ICH) is a major cause of morbidity and mortality in Japan. Seventeen Japanese institutions are participating in the Antihypertensive Treatment for Acute Cerebral Hemorrhage (ATACH) II Trial (ClinicalTrials.gov no. NCT01176565; UMIN 000006526). This phase III trial is designed to determine the therapeutic benefit of early intensive systolic blood pressure (BP) lowering for acute hypertension in ICH patients. This report explains the long run-up to reach the start of patient registration in ATACH II in Japan, including our preliminary study, a nationwide survey on antihypertensive treatment for acute ICH patients, a multicenter study for hyperacute BP lowering (the SAMURAI-ICH study), revision of the official Japanese label for intravenous nicardipine, and construction of the infrastructure for the trial.

Pretreatment ASPECTS on DWI predicts 3-month outcome following rt-PA: SAMURAI rt-PA Registry.

OBJECTIVE: To evaluate whether the pretreatment Alberta Stroke Programme Early CT Score (ASPECTS) assessed using diffusion-weighted imaging (DWI) predicts stroke outcomes at 3 months following IV recombinant tissue-type plasminogen activator (rt-PA) therapy. METHODS: Stroke patients treated with rt-PA (0.6 mg/kg alteplase) in 10 stroke centers in Japan were retrospectively studied. ASPECTS was assessed on DWI just prior to rt-PA injection. The primary outcome was a modified Rankin Scale (mRS) score of 0-2 at 3 months. Secondary outcomes included death at 3 months and symptomatic intracerebral hemorrhage (sICH) within 36 hours. RESULTS: For the 477 patients (316 men, 71 +/- 11 years old) enrolled, the median NIH Stroke Scale score was 13 (interquartile range 7-18.5), the median ASPECTS on DWI was 8 (7-10), and sICH was identified in 15 patients (3.1%). At 3 months, 245 (51.4%) had an mRS score of 0-2, and 29 (6.1%) had died. Patients with an mRS score of 0-2 had higher median ASPECTS (9; interquartile range 8-10) than other patients (8; 6-9, p < 0.001). Using receiver operating characteristic curves, the optimal cutoff ASPECTS to predict an mRS score of 0-2 was > or =7. On multivariate regression analysis, ASPECTS > or =7 was related to an mRS score of 0-2 (odds ratio 1.85; 95% confidence interval 1.07-3.24), ASPECTS < or =4 was related to death (3.61; 1.23-9.91), and ASPECTS < or =5 was related to sICH (4.74; 1.54-13.64). CONCLUSION: ASPECTS on DWI was independently predictive of functional and vital outcomes at 3 months, as well as sICH within 36 hours, following rt-PA therapy for stroke patients.

A study of vertebrobasilar artery dissection with subarachnoid hemorrhage.

We retrospectively studied clinical characteristics of 368 patients with cerebral artery dissections who were diagnosed in 172 Japanese hospitals. Of these patients, 130 (35%) presented with subarachnoid hemorrhage, 217 (59%) with cerebral infarctions, and 21 (6%) with transient ischemic attacks. We analyzed 109 (84%) subarachnoid hemorrhage cases caused by vertebrobasilar artery dissection to evaluate conservative and surgical treatment from the viewpoint of postoperative rerupture and infarction.Subsequent ruptures were observed in 14% of the 21 cases with nonsurgical treatment. For the preventive purpose of rerupture, 88 patients received surgical interventions: 68 trappings, 13 proximal occlusions, 6 aneurysmal sac occlusions and 1 stenting. Rerupture was experienced in 33% of the aneurysmal sac occlusion patients while not occurring in the other three surgical interventions. In the group without vascular anastomosis, postoperative cerebral infarction was observed in 25% of the trapping, none of the proximal occlusion and 33% of the aneurysmal sac occlusion cases.In this study, aneurysmal sac occlusion treatments were more frequently complicated by rerupture or cerebral infarction postoperatively than the other treatment methods. It was difficult to determine which surgical treatment can achieve better surgical outcome among the proximal occlusion and trapping with or without vascular anastomosis.

Arterial occlusion sites on magnetic resonance angiography influence the efficacy of intravenous low-dose (0.6 mg/kg) alteplase therapy for ischaemic stroke.

AIMS: To determine the predictors of efficacy, including magnetic resonance imaging information, for low-dose intravenous alteplase therapy for stroke patients. METHODS: Seventy-eight patients were prospectively enrolled in a single Stroke Unit (SU) receiving alteplase at a dose of 0.6 mg/kg during the initial 27 months after its approval in Japan. Ischaemic changes and vascular lesions were identified using computed tomography, diffusion-weighted magnetic resonance imaging, and magnetic resonance angiography. Early ischaemic signs were assessed using the Alberta Stroke Program Early CT Score. RESULTS: The median baseline National Institutes of Health Stroke Scale score of 78 patients was 12. In 19 patients (24%), the National Institutes of Health Stroke Scale score improved by >or=8 points at 24 h. After multivariate adjustment, occlusion at the internal carotid artery (odds ratio 11.82, 95% confidence interval 1.73-142.74), Alberta Stroke Program Early CT Score on diffusion-weighted imaging

Frontal bone window improves the ability of transcranial color-coded sonography to visualize the anterior cerebral artery of Asian patients with stroke.

The frontal bone window (FBW) is a promising approach in evaluating the anterior cerebral artery. The goal of the present study was to determine the rates of detection of the basal cerebral arteries by using the FBW alone and a combination of the FBW with the temporal bone window (TBW) in 163 patients. The combined application improved detection rates of A1 (58.6% versus 46.0%, P = .001) and A2 (43.6% versus 6.7%, P < .001) compared with the TBW alone.

Baseline NIH Stroke Scale Score predicting outcome in anterior and posterior circulation strokes.

OBJECTIVE: The NIH Stroke Scale (NIHSS) may not appropriately assess the spectrum of posterior circulation (PC)-related neurologic deficits. We determined the cutoff baseline NIHSS score that predicts independent daily life activity during the chronic stage in anterior circulation (AC) vs PC ischemic strokes. METHODS: A total of 310 consecutive patients hospitalized within 3 days after the onset of an ischemic stroke were prospectively enrolled in the study. Patients on thrombolytic therapy were excluded. In all patients, infarcts and vascular lesions were identified primarily using magnetic resonance techniques. A favorable outcome was defined as a modified Rankin Scale score of < or =2 at 3 months poststroke. RESULTS: In 101 patients with PC stroke, the total baseline NIHSS score was lower (p < 0.001), and the subscores of ataxia (p < 0.001) and visual fields (p = 0.043) were higher than in 209 patients with AC stroke. Multivariate-adjusted OR for the favorable outcome in patients with PC vs AC stroke was 2.339 (95% CI 1.331-4.109, p = 0.003). A low baseline NIHSS score was independently predictive of a favorable outcome in both patients with PC (OR 1.547, 95% CI 1.232-1.941) and AC (1.279, 1.188-1.376) stroke. The optimal cutoff scores of the baseline NIHSS for the favorable outcome were < or =5 for patients with PC stroke (sensitivity, 84%; specificity, 81%) and < or =8 for patients with AC stroke (sensitivity, 80%; specificity, 82%). CONCLUSIONS: The cutoff score of the baseline NIH Stroke Scale (NIHSS) for a favorable chronic outcome was relatively low in patients with PC stroke compared to patients with AC stroke. The NIHSS appears to have limitations with respect to its use when comparing the neurologic severity of PC and AC stroke.

Eccentric stenosis of the carotid artery associated with ipsilateral cerebrovascular events.

BACKGROUND AND PURPOSE: Eccentric stenosis of the coronary artery is associated with plaque disruption and acute coronary syndrome. The purpose of the present study was to determine whether eccentric stenosis of the carotid artery contributes to cerebrovascular events. MATERIALS AND METHODS: Of 6859 patients with vascular diseases who underwent duplex carotid ultrasonography, we studied 512 internal carotid arteries in 441 patients who had a maximum area stenosis at or more than 70%, which corresponds with approximately 50% or more by the NASCET method. The maximal (A) and minimal wall thicknesses (B) were measured on cross-sectional sonography images, and an eccentricity index was calculated using the following formula: (A - B)/A. Arteries in the lowest quartile of the eccentricity index (<0.69) were defined as having a concentric stenosis, whereas the others were defined as having eccentric stenosis. The underlying clinical characteristics and plaque morphologies, as well as the occurrence of ipsilateral ischemic stroke or transient ischemic attack in the preceding year, were compared between patients with eccentric and concentric stenosis. RESULTS: Patient characteristics and plaque morphology were similar between the 2 groups. Cerebrovascular events occurred more frequently ipsilaterally to the artery with eccentric stenosis (13.5%) than to the artery with concentric stenosis (5.5%; P = .013); the difference was more evident when cerebrovascular events of presumed carotid arterial origin were assessed (P = .005). After adjusting for risk factors and plaque morphology, eccentric stenosis was independently related to the presence of recent cerebrovascular events (odds ratio = 2.76; 95% confidence interval = 1.19-6.40). CONCLUSIONS: In patients with an area carotid stenosis of 70% or more, eccentric plaque was associated with a significantly increased incidence of ipsilateral cerebrovascular events compared with patients with concentric stenosis.

Association between signal hyperintensity on T1-weighted MR imaging of carotid plaques and ipsilateral ischemic events.

BACKGROUND AND PURPOSE: To investigate associations between cerebral ischemic events and signal hyperintensity in T1-weighted MR imaging (T1WI) of carotid plaque according to stenosis severity and to estimate persistence of T1WI signal hyperintensity. METHODS: A total of 222 patients (392 atherosclerotic carotid arteries) underwent plaque imaging using 3D inversion-recovery-based T1WI (magnetization-prepared rapid acquisition with gradient-echo [MPRAGE]). Carotid plaque with intensity on MPRAGE of >200% that of adjacent muscle was categorized as "high signal intensity" and correlated with ipsilateral ischemic events within the previous 6 months. A total of 58 arteries (35 patients) underwent repeat MR imaging a total of 70 times at a median interval of 279 days (range, 10-1037 days). RESULTS: Ipsilateral ischemic events were more frequent in patients with MPRAGE high signals than in patients with low signals in the 0%-29%, 30%-69%, and 70%-99% stenosis groups: Relative risk (95% confidence interval) was 2.50 (0.96-6.51), 7.55 (1.84-31.04), and 1.98 (1.01-3.90), respectively. In the 70 cases of repeat MR imaging, 29 of 30 cases with high signals on the preceding MR imaging maintained high signals. Of the 58 arteries that underwent repeat MR imaging, 4 of 22 carotid arteries with high signals developed ipsilateral subsequent ischemic events within 1 year, whereas none with low signals developed subsequent events. CONCLUSIONS: Carotid plaque signal hyperintensity on T1WI is strongly associated with previous ipsilateral ischemic events, persisting over a period of months, and may indicate risk of subsequent events. Larger clinical trials are warranted to clarify associations between signal hyperintensity and risk of subsequent cerebral ischemic events.

Glucose utilization in the inferior cerebellar vermis and ocular myoclonus.

In a patient with symptomatic ocular myoclonus, the authors observed the regional cerebral metabolic rate of glucose use (rCMRGlu) before and after successful treatment with clonazepam. Even after the symptoms resolved, the rCMRGlu in the hypertrophic olive increased persistently, whereas that in the inferior cerebellar vermis contralateral to the hypertrophic olive decreased. The inferior cerebellar vermis, belonging to the vestibulocerebellar system, may be associated with the generation of symptomatic ocular myoclonus.

Intermittent oro-esophageal tube feeding in acute stroke patients -- a pilot study.

OBJECTIVE: Acute stroke patients with dysphagia are usually fed by nasogastric tube. However, this method sometimes causes pneumonia or diarrhea. We investigated the use of a new feeding procedure called intermittent oro-esophageal (IOE) tube feeding in acute stroke patients with severe dysphagia. MATERIALS AND METHODS: The IOE method was used in 13 acute stroke patients (68 +/- 14 years old; 12 had a brainstem infarction), who were alert, but had severe dysphagia and a weak pharyngeal reflex. IOE tube feeding was carried out as follows. A feeding tube was passed orally into the lower portion of the esophagus, food supplements were administered through the tube at a rate of approximately 50 ml/min, and the tube was removed after finishing the supplement infusion. RESULTS: We found that the IOE method had the following advantages: (i) IOE feeding took approximately 15 min; (ii) potentially reduced a risk of complications such as pneumonia and diarrhea; and (iii) oral tube insertion stimulated the oral cavity and pharynx, which may improve the swallowing function. However, the IOE feeding method should not be used in patients who: (i) could not understand the IOE procedure; (ii) had an esophageal hiatal hernia or incomplete peristalsis of the esophagus, as such patients are at risk of having the supplement reflux into the oral cavity. CONCLUSION: The IOE feeding method may be one of the alternatives to continuous nasogastric tube feeding in acute stroke patients with severe dysphagia, who are alert.

Antiplatelet therapy contributes to acute deterioration of intracerebral hemorrhage.

OBJECTIVE: The purpose of this study was to examine the effect of antiplatelet therapy on the initial severity and the acute outcome of intracerebral hemorrhage (ICH). METHODS: The authors reviewed records of 251 consecutive patients hospitalized in their cerebrovascular center within 24 hours after onset of ICH. RESULTS: Fifty-seven patients (23%) had development of ICH during oral antiplatelet therapy. The major indication for antiplatelet therapy was the prevention of stroke recurrence (63%). As compared with patients without antiplatelet therapy, those who received antiplatelet therapy more frequently were aged 70 years or older (60% vs 35%; p < 0.001), had previous symptomatic ischemic stroke (54% vs 7%; p < 0.0001), had diabetes mellitus (26% vs 15%; p < 0.05), and had heart disease (32% vs 8%; p < 0.0001). Antiplatelet therapy was predictive of an increase in the hematoma volume by more than 40% on the second hospital day (hematoma enlargement, odds ratio [OR] 7.67, 95% CI 1.62 to 36.4) and the need for emergent surgical evacuation of the hematoma (OR 3.10, 95% CI 1.18 to 8.15). Antiplatelet therapy was an independent predictor for the occurrence of any of hematoma enlargement, emergent death, or evacuation surgery, which suggests that clinical deterioration occurs into the second hospital day (OR 7.45, 95% CI 2.46 to 22.5). CONCLUSIONS: Antiplatelet therapy seems to contribute to the acute clinical deterioration of intracerebral hemorrhage.

Atrial fibrillation as a predictive factor for severe stroke and early death in 15,831 patients with acute ischaemic stroke.

BACKGROUND: Atrial fibrillation (AF) is a common arrhythmia and a major risk factor for stroke. AIMS: To assess whether AF in patients with acute ischaemic stroke is associated with severe stroke and early death. MATERIALS/METHODS: Patients with acute ischaemic stroke (15,831) who were registered in the Japan Multicenter Stroke Investigators' Collaboration registry were analysed. The AF group comprised 3335 (21.1%) patients (median age, 75 years) and the non-AF group comprised 12,496 (78.9%) patients (median age, 70 years). The association between AF and severe stroke and early death was investigated by means of multivariate logistic regression analysis. RESULTS: The admission National Institutes of Health Stroke Scale (NIHSS) score of the AF group was higher than that of the non-AF group (median, 12 v 5; p < 0.0001). Multivariate logistic regression analyses found that female sex, advanced age, AF, and a history of stroke were independent factors associated with severe stroke (NIHSS score, > or = 11). The mortality rate within 28 days after admission was 11.3% in the AF group and 3.4% in the non-AF group (p < 0.0001). Multivariate logistic regression analyses identified older age, AF, and NIHSS score at admission as independent factors associated with early death. CONCLUSION: AF was a predictive factor for severe stroke and early death in acute ischaemic stroke. Careful cardiac evaluation and appropriate treatment are needed to improve outcome in patients with acute stroke and AF.

Isolated pulmonary arteriovenous fistula without Rendu-Osler-Weber disease as a cause of cryptogenic stroke.

There has been uncertainty as to whether a right to left shunt through an isolated pulmonary arteriovenous fistula (P-AVF) without Rendu-Osler-Weber (ROW) disease can cause paradoxical brain embolism. A population of 747 acute ischaemic stroke patients was examined to determine the frequency and clinical characteristics of those patients who had an isolated P-AVF. The presence of a P-AVF was determined as follows. On patients with a stroke of undetermined cause, both transoesophageal echocardiography and transcranial Doppler with saline contrast medium was performed to detect a right to left shunt. If a P-AVF was then suspected, selective pulmonary angiography and enhanced chest CT was performed to confirm the presence of the P-AVF. Four patients (0.5%) were diagnosed as having a stroke associated with an isolated P-AVF. All the patients were middle-aged women (mean age 61 years). In all these patients, the P-AVF could not have been suspected on physical findings or chest x ray. The P-AVF was always single and located in the lower lobe. All the patients had asymptomatic deep venous thrombosis, and three patients developed pulmonary embolism. As D-dimer and thrombin-antithrombin complex were elevated in all patients, this indicated an activation of both fibrinolytic and thrombin activity. Our results show that an isolated P-AVF without ROW disease can cause paradoxical brain embolism. Thus, the existence of an isolated P-AVF as a right to left shunt in patients with a stroke of unknown origin should not be overlooked, even if a P-AVF is not suggested by the initial physical findings or chest x ray.